4220-01-174-0997 (3900-53)
4220-01-174-0997 is equivalent to manufacture part number 3900-53. It is a mask side valve and is classified under Federal Supply Class 4220 (4220 - Marine Lifesaving and Diving Equipment), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 4220 - Marine Lifesaving and Diving Equipment and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.